THE BRITISH TAWNY OWE. 91 



Middle-sized and large, very thick-headed Owls without ear- 

 tufts. Eyes very large. Ear-openings large, very asymmetrical, 

 i.e. right ear larger and of different shape than left, with a large 

 operculum or skin -flap, but no transverse fold. Wings compara- 

 tively short, but wide, 4th and 5th, or 3rd, 4th and 5th primaries 

 longest, first 5 or 6 sinuated on inner webs. Tail rounded. Toes 

 feathered except at utmost end. Over 20 species, some with num- 

 ber of subspecies ; Palsearctic region and well into tropics (China, 

 Formosa), and America. 



STRIX ALUCO 



239. Strix aluco sylvatica Shaw.— THE BRITISH TAWNY 

 OWL.* 



Strix sylvatica Shaw, Gen. Zool., vn, p. 253 (1809 — New name for 

 the English " Wood Owl "). 



Strix aluco Linnaeus, Yarrell, 1, p. 146 ; Syrnium aluco (Linnaeus), Saunders, 

 p. 297 : Strix aluco aluco L., Hand-List Brit. B. (1912), p. 109. 



Description (Plates 1 and 2). — Adult male and female. Winter. — 

 General colour of upper -parts tawny (occasionally rich chestnut- 

 tawny), tawny-burr, huffish-brown or greyish -brown but very rarely 

 in British birds greyish -white, streaked and freckled blackish-brown. 

 In brown examples feathers on sides of crown and mantle have 

 white or bumsh-white subterminal spots or rounded marks varying 

 in shape and size, but in tawny examples these are not so conspicuous 

 as they are more buff or tawny ; each feather of upper -parts with 

 blackish -brown to dark brown mesial streak and wavy cross-bars, 

 varying in individuals but wider and more conspicuous on crown 

 and mantle and narrower and not so strongly marked on back, 

 rump and upper tail-coverts ; outer scapulars with most of their 

 outer webs except at base and tip (which is blackish) silky -white, 

 sometimes tinged buff, forming a line of conspicuous white 

 " mirrors " ; facial disk, which is complete, dull white, feathers of 

 loral portion with black tips and of rest of disk in tawny specimens 

 with considerable amount of rufous, in brown examples with only 

 a tinge of rufous and spotted and barred with brown, in grey 

 examples no rufous and more distinctly spotted and barred dark 

 brown, feathers of " ruff " black-brown centrally mottled buff to 

 whitish at tips, those of lower part of "ruff " usually more whitish 

 and with dark cross-bars and in centre of chin always marked 

 rufous even in greyest examples ; under -parts white to pale buff, 

 rufous examples suffused with buff on breast and flanks, but whitish 



* The British Tawny Owl is distinguished from the typical Continental 

 form by its smaller size: wing, males, British 245-270 mm., Continental 

 265-200; females British 255-275, Continental 270-305. Also the British 

 bird is seldom grey, whereas in Continental birds grey are commoner than 

 tawny individuals. — H.F.W., E.H. 



